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level, till it enters the meadow ? And can 

 you draw the water off your meadow as 

 quick as it is brought on ? If these ques-* 

 tions suggest no insuperable difficulty^ 

 but can freely be answered in the affirma- 

 tive, you may proceed according to the 

 following directions : 



In the first place, when the descent i» 

 liot sufficiently great to be determined by 

 the eye, take an accurate level of the 

 ground intended for floating, and compare 

 the highest part of it with the height of 

 the stream of water to be used. Ascer- 

 tain how many inches fall there are, from 

 the surface of the water, to the highest 

 part of the land : if the highest part of 

 the land be adjoining to the stream, the 

 process is easy ; but if, as it often hap- 

 pens, it be distant from (or the farthest 

 part from) the stream, the execution be- 

 come* 



